1. Field of the Invention
The present invention relates to a surveying system, for which staking out or laying off can be carried out. Further, the invention also relates to a surveying system, which can also process measurement information within the system.
2. Description of the Related Art
In conventional route surveying or site surveying, which involves staking out operations, at least two persons are required. Namely, one person operates a surveying instrument provided with a staking out function, while the other person searches for a staking point with a target, such as a prism or the like. Position data for a plurality of given points, where substantial or actual positions are known, and staking points are pre-installed in a surveying instrument, such as a total station or the like. For example, the surveying instrument is positioned at a second given point with respect to a direction from a first given point, known as a back sight direction. The horizontal angle and the horizontal distance from the instrument point to a staking point with respect to the first given point is indicated on the surveying instrument. The person with the prism or target should stand at about a position that is expected to be near an objective staking point, while the other person measures the position of the prism or target, with the surveying instrument and detects the difference from the position of the objective staking point, so as to instruct the person with the prism or target which direction the prism or target should be moved, by using two-way or gestures. This operation is repeated until the difference between the target and the position of a preset staking point becomes sufficiently small for the two points to be regarded as at equal positions, so that a stake is properly positioned. Further, when a recently developed surveying instrument with an automatic sighting function is used, the above explained staking out surveying can be achieved by one person. Namely, the surveying instrument automatically aims at the prism or target that is held by one staking operator and instructs the operator regarding which direction to move, by sending measurement data via a wireless telecommunication system or through optical signals. The staking operator may seek the given staking point with reference to the transmitted measurement data or the optical signals and move the prism or target.
However, the above surveying operations involving one or two people are cumbersome and require time, since a staking operator is lead to a given staking point by using words and gestures, so that the position of a staking point is not clear for the staking operator. Even when using an automatic sighting surveying instrument, it is still difficult to obtain a proper position of a staking point visually and spatially, so that searching for a given staking point is difficult. Further, when there are a substantial number of measurement points, an unmeasured measurement point might be confused with a measurement point that has already been measured.
Further, in conventional surveying or measurement practice, a picture or image of a surveying area including stations (points which are to be measured) may be taken and recorded with the measurement data on some occasions. On these occasions, an image of a surveying area may be photographed with a separate normal camera not associated with the surveying instruments or with an imaging device integrally installed inside the surveying instruments, as described in Japanese unexamined patent publication No. 11-337336. In this publication, images are captured for each of the measurement points.
However, when an image is taken with a separate normal camera, measurement points are not indicated on the image, so that it is impossible for a user to identify the points on the image that correspond to each of the measurement points. On the other hand, when utilizing a surveying instrument disclosed in the above unexamined patent publication '336, a large-capacity memory is required, since images are captured and stored for each of the measurement points, which in turn causes operating difficulties for a user.